Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases. Notes: It is intended for this problem to be spe…

题意:字符串转正数 原题来自:https://leetcode.com/problems/string-to-integer-atoi/ 分析: <程序员面试宝典>上出现的面试题,主要是考虑到细节. 1. 字串为空或者全是空格,返回0: 2. 字串的前缀空格需要忽略掉: 3. 忽略掉前缀空格后,遇到的第一个字符,如果是‘+’或‘-’号,继续往后读:如果是数字,则开始处理数字:如果不是前面的2种,返回0: 4. 处理数字的过程中,如果之后的字符非数字,就停止转换,返回当前值: 5. 在上述处理过…

Given an array of characters, compress it in-place. The length after compression must always be smaller than or equal to the original array. Every element of the array should be a character (not int) of length 1. After you are done modifying the inpu…

String to Integer (atoi) Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases. Notes: It is intended f…

原题链接在这里:https://leetcode.com/problems/string-compression/description/ 题目: Given an array of characters, compress it in-place. The length after compression must always be smaller than or equal to the original array. Every element of the array should b…

目录 3无重复字符的最长子串 5最长回文子串 8字符串转换整数(atoi), 9回文数,7整数反转 28实现strStr(), 459重复的子字符串(KMP) 43字符串相乘 71简化路径 93复原IP地址 60第k个排列 151翻转字符串里的单词(344反转字符串.557反转字符串中的单词 III) 14最长公共前缀 20有效的括号 567字符串的排列(了解) 3无重复字符的最长子串 思路: 新建数组int[128],用来记录各个字符处在字符串中的最新位置.注意位置从1开始,一方面区别默认的0…

刚看到题就想用数组做,发现大多数解也是用数组做的,突然看到一个清新脱俗的解法: int atoi(const char *str) { ; int n; string s(str); istringstream iss(s); iss>>n; return n; } 代码简洁,核心使用的是istringstream C++串流输入类,该类对象能把字符串对象str读出字符并写入到自定义的各种类型变量中.…

Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases. Notes: It is intended for this problem to be spe…

引言 在字符串类型的题目中,常常在解题的时候涉及到大量的字符串的两两比较,比如要统计某一个字符串出现的次数.如果每次比较都通过挨个字符比较的方式,那么毫无疑问是非常占用时间的,因此在一些情况下,我们可以将字符串本身作为hashmap的key,往往会大大节省时间. 这篇博文中涉及的另一个技巧,是使用窗口的思想,这种思想不单单在字符串类型的题目中使用.这个技巧简单说来就是维护两个int,start和end,作为窗口的左右端.在不断的向前移动end和start的时候,记录下窗口包含的最大长度和最小长度…

Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases. Notes: It is intended for this problem to be spe…